Study Objective: To develop a preoperative calculator to predict the total operative time (TOT) for robotic-assisted laparoscopic myomectomy (RALM). Design: Retrospective cross-sectional study. Setting: University medical center. Patients: Women who underwent RALM performed by 3 high-volume surgeons at a single institution between January 2014 and December 2017. Interventions: Demographic characteristics, indication for surgery, surgical history, myoma burden on imaging, and TOT were collected. RALM operative time was classified as <3 hours, 3 to 5 hours, and >5 hours. We identified preoperative characteristics predictive of increased operative time and developed a preoperative calculator to estimate TOT. Measurements and Main Results: A total of 126 women underwent RALM during the study period, with a mean TOT of 213 minutes § 66 minutes. The mean total weight of myomas removed was 264 g § 236 g, and mean largest myoma diameter was 8.5 cm § 2.6 cm. Overall, mean number of myomas removed was 2.5 § 2.4, and estimated blood loss (EBL) was 215 § 212 mL. Five patients (4.0%) received a blood transfusion, and 4 patients (3.2%) underwent conversion to laparotomy. Preoperative factors significantly associated with TOT included patient age, personal history of diabetes mellitus, uterine volume, number of myomas, number of myomas >3 cm, diameter of the dominant myoma, and surgeon experience. The mean uterine volume was 282 cm 3 for procedures with a TOT <3 hours, 461 cm 3 for procedures with a TOT of 3 to 5 hours, and 532 cm 3 for procedures with a TOT >5 hours (p = .004). Body mass index, personal history of hypertension, previous abdominal/pelvic surgery, surgical indication, location of dominant myoma (anterior, posterior, or fundal) and classification of dominant myoma (submucosal, intramural, subserosal, or other) were not associated with TOT. Our preoperative calculator correctly predicted TOT category in 88% of the patients and estimated TOT within a 1-hour margin in 80% of patients. Conclusion: RALM is becoming a more popular surgical approach for the management of uterine myomas. Preoperative radiographic evaluation and a thorough patient history may enhance patient counseling and surgical planning. Uterine volume and myoma number and size appear to be more predictive of TOT compared with myoma location.